Merge commit '8e97373d883c06e1c73791849561d1311c880bc0' as 'libs/loguru'

libs/loguru/loguru_bench/CMakeLists.txt

@@ -0,0 +1,22 @@
+cmake_minimum_required(VERSION 2.8)
+
+project(loguru_bench)
+
+if(NOT CMAKE_BUILD_TYPE)
+  set(CMAKE_BUILD_TYPE "Release" CACHE STRING
+      "Choose the type of build, options are: Debug Release RelWithDebInfo MinSizeRel." FORCE)
+endif(NOT CMAKE_BUILD_TYPE)
+
+MESSAGE(STATUS "CMAKE_BUILD_TYPE: ${CMAKE_BUILD_TYPE}")
+
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -Werror -Wall -Wextra")
+
+file(GLOB source
+    "${CMAKE_CURRENT_SOURCE_DIR}/*.cpp"
+)
+
+add_executable(loguru_bench ${source})
+
+find_package(Threads)
+target_link_libraries(loguru_bench ${CMAKE_THREAD_LIBS_INIT}) # For pthreads
+target_link_libraries(loguru_bench dl) # For ldl

libs/loguru/loguru_bench/build_and_run.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+set -e # Fail on error
+
+ROOT_DIR=$(cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd)
+
+cd "$ROOT_DIR"
+mkdir -p build
+cd build
+cmake ..
+make
+
+./loguru_bench $@ 2>/dev/null

libs/loguru/loguru_bench/loguru_bench.cpp

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+#include <chrono>
+#include <cmath>
+#include <iomanip>
+#include <iostream>
+#include <vector>
+
+#define LOGURU_WITH_STREAMS 1
+#define LOGURU_REDEFINE_ASSERT 1
+#include "../loguru.cpp"
+
+const size_t kNumRuns = 10;
+const double kPi = 3.1415926535897932384626433;
+
+static long long now_ns()
+{
+	using namespace std::chrono;
+	return duration_cast<nanoseconds>(high_resolution_clock::now().time_since_epoch()).count();
+}
+
+template<typename Function>
+void bench(const std::string& name, const Function& function, size_t num_iterations)
+{
+	function(num_iterations); // Warm-up.
+
+	printf("%-30s ", name.c_str());
+	fflush(stdout);
+	std::vector<double> times;
+	double sum = 0;
+	for (size_t i = 0; i < kNumRuns; ++i) {
+		auto start_ns = now_ns();
+		function(num_iterations);
+		double total_time_sec = (now_ns() - start_ns) * 1e-9;
+		times.push_back(total_time_sec / num_iterations);
+		sum += times.back();
+	}
+
+	double mean = sum / kNumRuns;
+	double std_dev_sum = 0;
+
+	for (double time : times) {
+		std_dev_sum += (time - mean) * (time - mean);
+	}
+
+	double variance = std::sqrt(std_dev_sum / kNumRuns);
+
+	printf("%6.3f ± %.3f μs per call\n", mean * 1e6, variance * 1e6);
+	fflush(stdout);
+}
+
+// ----------------------------------------------------------------------------
+
+void format_strings(size_t num_iterations)
+{
+	for (size_t i = 0; i < num_iterations; ++i) {
+		LOG_F(WARNING, "Some long, complex message.");
+	}
+	loguru::flush();
+}
+
+void format_float(size_t num_iterations)
+{
+	for (size_t i = 0; i < num_iterations; ++i) {
+		LOG_F(WARNING, "%+05.3f", kPi);
+	}
+	loguru::flush();
+}
+
+void stream_strings(size_t num_iterations)
+{
+	for (size_t i = 0; i < num_iterations; ++i) {
+		LOG_S(WARNING) << "Some long, complex message.";
+	}
+	loguru::flush();
+}
+
+void stream_float(size_t num_iterations)
+{
+	for (size_t i = 0; i < num_iterations; ++i) {
+		LOG_S(WARNING) << std::setfill('0') << std::setw(5) << std::setprecision(3) << kPi;
+	}
+	loguru::flush();
+}
+
+void raw_string_float(size_t num_iterations)
+{
+	for (size_t i = 0; i < num_iterations; ++i) {
+		RAW_LOG_F(WARNING, "Some long, complex message.");
+	}
+	loguru::flush();
+}
+
+void error_context(size_t num_iterations)
+{
+	for (size_t i = 0; i < num_iterations; ++i) {
+		ERROR_CONTEXT("key", "value");
+	}
+}
+
+int main(int argc, char* argv[])
+{
+	const size_t kNumIterations = 50 * 1000;
+
+	loguru::init(argc, argv);
+	loguru::add_file("loguru_bench.log", loguru::Truncate, loguru::Verbosity_INFO);
+
+	bench("ERROR_CONTEXT", error_context, kNumIterations * 100);
+
+	loguru::g_flush_interval_ms = 200;
+	bench("LOG_F string (buffered):", format_strings,   kNumIterations);
+	bench("LOG_F float  (buffered):", format_float,     kNumIterations);
+	bench("LOG_S string (buffered):", stream_strings,   kNumIterations);
+	bench("LOG_S float  (buffered):", stream_float,     kNumIterations);
+	bench("RAW_LOG_F    (buffered):", raw_string_float, kNumIterations);
+
+	loguru::g_flush_interval_ms = 0;
+	bench("LOG_F string (unbuffered):", format_strings,   kNumIterations);
+	bench("LOG_F float  (unbuffered):", format_float,     kNumIterations);
+	bench("LOG_S string (unbuffered):", stream_strings,   kNumIterations);
+	bench("LOG_S float  (unbuffered):", stream_float,     kNumIterations);
+	bench("RAW_LOG_F    (unbuffered):", raw_string_float, kNumIterations);
+}